System and method for cooling or heating a human body part

ABSTRACT

A system for cooling or heating a body part includes at least one bladder, a pump, a heat exchanger, a first fluid line in fluid communication with the heat exchanger and the at least one bladder, a second fluid line in fluid communication with the at least one bladder and the heat exchanger, a main reservoir and a separator. The heat exchanger is in fluid communication with the pump. The first fluid line is located downstream from the heat exchanger and the second fluid line is located downstream from the at least one bladder when the system is operating to cool or heat the body part. The separator is in fluid communication with the main reservoir and the pump and is located below the main reservoir to receive fluid under the influence of gravity from the main reservoir and to deliver fluid to the pump via gravity.

BACKGROUND

U.S. Pat. No. 6,183,501 B1 discloses a cooling system having a head andneck device which can be cooled to reduce trauma to the brain. The headdevice includes panels that each house a cold element to facilitatecooling. The head device secures to the head of an individual and coversover the individual's carotid arteries, which provide blood to thebrain. US 2012/0288848 A1 discloses similar devices connected with apump and cooling fluid source.

The pump and cooling fluid liquid sources have been described as areservoir surrounded by a cooling unit which is supplied refrigerantfrom a compressor, for example in U.S. Pat. No. 6,511,502 B2. Ice bathsin which ice has been placed into a reservoir of water have also beenused as a cooling fluid source.

BRIEF DESCRIPTION

In view of the foregoing, a system for cooling or heating a body partincludes at least one bladder, a pump, a heat exchanger, a first fluidline in fluid communication with the heat exchanger and the at least onebladder, a second fluid line in fluid communication with the at leastone bladder and the heat exchanger, a main reservoir and a separator.The at least one bladder is configured to be placed on a body part. Theheat exchanger is in fluid communication with the pump. The first fluidline is located downstream from the heat exchanger and the second fluidline is located downstream from the at least one bladder when the systemis operating to cool or heat the body part. The separator is in fluidcommunication with the main reservoir and the pump and is located belowthe main reservoir to receive fluid under the influence of gravity fromthe main reservoir and to deliver fluid to the pump via gravity.

A unit for providing heated or cooled fluid to an associated bladder tobe placed on a body part includes a casing, a pump positioned in thecasing, a heat exchanger positioned in the casing, a unit outlet influid communication the heat exchanger, a unit inlet in fluidcommunication with the heat exchanger, a main reservoir positioned in oron the casing and a separator positioned in the casing between and influid communication with the main reservoir and the pump. The heatexchanger is in fluid communication with the pump. The unit outlet ispositioned with respect to the heat exchanger to receive fluid that haspassed through the heat exchanger. The unit inlet is positioned withrespect to the heat exchanger to provide fluid to the heat exchanger.The separator is located below the main reservoir to receive fluid underthe influence of gravity from the main reservoir. The separator is alsolocated with respect to the pump so as to deliver fluid from theseparator to the pump under the influence of gravity. The separator hasa volumetric space toward a top of the separator for allowing airbubbles to migrate toward the volumetric space to inhibit air fromentering into the pump.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic depiction of a system for cooling or heating abody part.

FIG. 2 is a cross-sectional view taken through an example of a unit ofthe system shown in FIG. 1.

DETAILED DESCRIPTION

FIG. 1 schematically depicts a system 10 for heating or cooling a bodypart, such as the head, neck, knee, or other areas of the human bodyincluding internal organs such as the brain. The system 10 generallyincludes at least one bladder 12 that connects to a unit 14, which canbe a chiller unit or a heater unit, through a first fluid line 16 and asecond fluid line 18. When the system 10 is operating to cool a bodypart, relatively cooler fluid passes from the unit 14 through the firstfluid line 16 toward the bladder 12. The relatively cooler fluid is thenwarmed when the bladder 12 is brought in proximity to the human bodypart. Relatively warmer water then exists the bladder 12 and travelstoward the unit 14 through the second fluid line 18 to again be cooledfor delivery back to the bladder 12. The first and second fluid lines16, 18 are schematically depicted in FIG. 1 and can include flexibleplastic tubing in single or multiple sections having fittings orconnectors at each end for connecting with the unit 14 and the bladder12, respectively.

The unit 14 generally includes a casing 30, a pump 32 positioned in thecasing 30, a heat exchanger 34 positioned in the casing, a unit outlet36 in fluid communication with the heat exchanger 34, a unit inlet 38also in fluid communication with the heat exchanger 34, a main reservoir40 positioned in or on the casing 30, and a separator 42 positioned inthe casing 30 between and in fluid communication with the main reservoir40 and the pump 32. The unit 22 is designed to be a portable unit thatcan be easily lifted by a healthy adult. With reference to FIG. 2, theunit 14 can be provided with a handle 44 to allow the unit 14 to beeasily carried.

As mentioned above, the casing 30 houses many of the internal componentsof the unit 14. The casing 30 in the illustrated embodiment is made froma durable plastic material; however, the casing could be made from othermaterial durable materials.

With reference to FIG. 2, the pump 32 is positioned near a lower wall 50of the casing 30. With reference back to FIG. 1, the pump 32 includes apump inlet 52 and a pump outlet 54. In the illustrated embodiment, thepump 32 is a centrifugal pump; however, other types of pumps could beused such as positive displacement pumps and the like. The pump 32 drawsfluid from the unit inlet 38 through the pump inlet 52 and then out thepump outlet 54.

The heat exchanger 34 is in fluid communication with the pump 32. Theheat exchanger 34 is schematically depicted as a cooler in FIG. 2 andwill be described as such as part of a cooling system; however, the heatexchanger could also operate as a heater. In the illustrated embodiment,the heat exchanger 34 is positioned downstream from the pump 32 when thesystem 10 is operating to cool or heat a body part. A valve 60 can beprovided downstream from the pump 32. The valve 60 can be opened when itis desirable to have fluid bypass the heat exchanger 34. The valve 60can be provided on a valve bypass line 62 that connects with the pump 32upstream from the heat exchanger 34 and then reconnects downstream fromthe heat exchanger 34. Operation of the valve 60 can be controlled by acontroller 64 that is in electrical communication with the valve 60 anda thermometer 66. Opening and closing of the valve 60 can be controlledbased on temperature readings provided by the thermometer 66 to thecontroller 64 so as to provide fluid at a desired temperature exitingthe unit 14 through the unit outlet 36.

In operation, when a body part is to be cooled, the bladder 12 is placedon the body part to be cooled, and the unit 14 is turned on so that apower source 68 provides power to the controller 64 and other internalcomponents of the unit 14, such as the pump 32, the heat exchanger 34,the valve 60 and the thermometer 66. The pump 32 pumps fluid so as toexit the pump outlet 54 and travel towards the heat exchanger 34. Whenthe unit 14 is operating as a chiller unit, heat is removed from thefluid resulting in a relatively cooler fluid exiting the heat exchanger34. The relatively cooler fluid then exits the unit 14 by way of theunit outlet 36 and travels through the first fluid line 16 toward thebladder 12. The relatively cooler fluid travels through the bladder 12and removes heat from the body part on which the bladder 12 rests.Relatively warmer water then exits the bladder 12 and travels throughthe second fluid line 18 back toward the pump 32. Fluid within the firstfluid line 16, the bladder 12, the second fluid line 18, and travelingthrough the unit 14 between the unit inlet 38 and the unit outlet 36operates in a closed circuit in that the circuit is not typically ventedor open to ambient. The total volume of fluid passing through thebladder 12, the fluid lines 16, 18, and the unit 14 between the unitinlet 38 and the unit outlet 36 can be referred to as a circuit volume.

The unit 14 further includes the main reservoir 40 located adjacent atop wall 70 of the casing 30. The main reservoir 40 can be positioned inor on the casing 30. The main reservoir 40 has a maximum main reservoirvolume at least five times greater than the circuit volume. By onlycooling (or heating) the volume of fluid required to provide the desiredtemperature in the bladder 12 in a closed circuit, i.e., by cooling orheating fluid in the circuit volume, less energy is required to operatethe heat exchanger 34 and the pump 32 as compared to if fluid in themain reservoir 40 was also being cooled or heated, which results in amore economical and environmentally friendly unit 14.

The main reservoir 40 includes a main reservoir outlet 80 and a mainreservoir inlet 82. The main reservoir 40 is provided inside the casing30 of the unit 14 in the illustrated embodiment; however, the mainreservoir 40 could also be provided on or connected with the casing 30.As mentioned above, the maximum main reservoir volume is much greaterthan the circuit volume, i.e., the volume of the fluid traveling fromthe unit 14 to the bladder 12 and then back to the unit 14. The maximummain reservoir volume can be five time or even ten times greater thanthe circuit volume. In the illustrated embodiment, a main reservoiroutlet line 84 connects with the main reservoir outlet 80. A vented cap86 selectively closes the main reservoir inlet 82. The vented cap 86 isconnectable with at least one of the casing 30 and the main reservoir 40for closing the main reservoir inlet 82. With reference to theembodiment illustrated in FIG. 2, the vented cap 86 threads onto a neck(not visible) that extends through an opening in the top wall 70 of thecasing 30.

As illustrated, the separator 42 is in fluid communication with the mainreservoir 40 and the pump 32 and is positioned below the main reservoir40 to receive fluid under the influence of gravity from the mainreservoir 40 via the main reservoir outlet line 84. As mentioned above,the pump 32 in the illustrated embodiment is a centrifugal pump.Centrifugal pumps are known to have difficulty priming. Fluid within themain reservoir 40 is fed to the separator 42 via gravity and theseparator 42 is located with respect to the pump 32 so as to deliverfluid from the separator 42 to the pump 32 under the influence ofgravity. This mitigates issues with regard to priming the pump 32because the pump 32 is positioned below the main reservoir 40 so thatthe head pressure of the fluid within the main reservoir 40 forces thefluid through the separator 42 and into the pump inlet 52 to mitigatepriming and cavitation issues in the pump 32.

The separator 42 has a separator inlet 92 connected with the mainreservoir outlet line 84. The separator 42 has a maximum volume that issmaller than the maximum main reservoir volume. As more clearly seen inFIG. 2, in the illustrated embodiment, the separator 42 also defines avolumetric space 94, which is exaggerated in FIG. 2, inside theseparator 42 that is offset from the separator inlet 92 for allowing airbubbles to migrate toward a top of the separator 42 without passing intothe main reservoir outlet line 84. This reduces the likelihood of airbubbles exiting the separator 42 through a separator outlet 96 andentering the pump 32, which can result in priming problems for the pump32, and also reduces the likelihood of air bubbles traveling through thepump 32 and into the fluid lines 16, 18 and the bladder 12. Withcontinued reference to FIG. 2, the separator 42 has a largercross-sectional area (taken normal to an axis along which the mainreservoir outlet line 84 extends) as compared to a cross-sectional areaof the main reservoir outlet line 84. This allows for the volumetricspace 94 in which the air bubbles can migrate within the separator 42without having to travel through the more constricted cross-sectionalarea of the main reservoir outlet line 84. The main reservoir 40 doeshave the vented cap 86 covering the main reservoir inlet 82, which canallow air to escape from the main reservoir 40. However, air bubbleswould have to overcome the pressure of any fluid within the mainreservoir 40 pressing against any fluid in the main reservoir outletline 84 before reaching the vented cap 86.

Fluid passing through the unit 14 from the unit inlet 38, through thepump 32 and the heat exchanger 34 and then through the unit outlet 36,along with traveling through the fluid lines 16, 18 and the bladder 12will inevitably result in fluid loss due to small leaks or transmissiveloss through the bladder 12 and the fluid lines 16, 18 connecting thebladder 12 to the unit 14. This lost fluid is replaced by fluid residingin the separator 42, and the fluid lost in the separator 42 is replacedby fluid that resides within the main reservoir 40. The pump 32, theunit inlet 38, and the separator 42 are configured and positioned in thecasing 30 such that the pump 32 primarily draws fluid from the unitinlet 38 and fluid is drawn from the separator 42 by the pump 32 onlywhen fluid is lost from the circuit volume. Again, only fluid passingthrough the relatively closed circuit between the unit 14 and thebladder 12 is cooled or heated by the heat exchanger 34 and the fluidwithin the main reservoir 40 typically stays at near ambienttemperature.

A sensor 100 is provided to monitor electrical current being drawn bythe pump 32. When no more fluid is provided by the separator 42 to thepump 32, the current draw by the pump 32 will spike, and the sensor 100can detect this state and provide an electrical signal to the controller64 which can stop delivery of electrical power to the pump 32 andprovide an indication to the operator that more fluid is needed in themain reservoir 40.

A system for cooling or heating a body part and a unit for use in such asystem have been described above with particularity. Modifications andalterations will occur to those upon reading and understanding thepreceding detailed description. The invention, however, is not limitedto only the system described above. Instead, the invention is broadlydefined by the appended claims and the equivalents thereof. Also,various presently unforeseen or unanticipated alternatives,modifications, variations or improvements may be subsequently made bythose skilled in the art which are also intended to be encompassed bythe following claims.

1. A system for cooling or heating a body part, the system comprising:at least one bladder configured to be placed on a body part; a pumpincluding a pump inlet and a pump outlet; a heat exchanger in fluidcommunication with the pump; a first fluid line in fluid communicationwith the heat exchanger and the at least one bladder, the first fluidline being located downstream from the heat exchanger when the system isoperating to cool or heat the body part; a second fluid line in fluidcommunication with the at least one bladder and the heat exchanger, thesecond fluid line being located downstream from the at least one bladderwhen the system is operating to cool or heat the body part; a mainreservoir; and a separator in fluid communication with the mainreservoir and the pump, the separator being located below the mainreservoir to receive fluid under the influence of gravity from the mainreservoir and to deliver fluid to the pump via gravity and head pressureof the fluid within the main reservoir forces the fluid through theseparator and into the pump inlet prior to the fluid from the separatorentering either the first fluid line or the second fluid line.
 2. Thesystem of claim 1, further comprising a main reservoir outlet lineconnected with an outlet of the main reservoir, wherein the separatorhas a separator inlet connected with the main reservoir outlet line anddefines volumetric space for allowing air bubbles to migrate toward atop of the separator without passing into the main reservoir outletline.
 3. The system of claim 2, wherein the separator has a largercross-sectional area as compared to a cross-sectional area of the mainreservoir outlet line.
 4. The system of claim 1, wherein the pump is acentrifugal pump.
 5. The system of claim 4, further comprising a sensorconfigured to detect electrical current being drawn by the pump.
 6. Thesystem claim 1, wherein the main reservoir has a maximum main reservoirvolume and a total volume of fluid circulating among the at least onebladder, the pump, the first fluid line, the second fluid line and theheat exchanger is a circuit volume, wherein the maximum main reservoirvolume is at least 5 times greater than the circuit volume.
 7. Thesystem of claim 6, wherein the maximum main reservoir volume is at least10 times greater than the circuit volume.
 8. The system of claim 1,further comprising a main reservoir outlet line connected with an outletof the main reservoir, wherein the main reservoir has a maximum mainreservoir volume and the separator has a maximum separator volume, whichis smaller than the maximum main reservoir volume.
 9. The system ofclaim 1, wherein the pump is upstream from the heat exchanger.
 10. Thesystem of claim 1, further comprising a casing, wherein the pump, theheat exchanger, the main reservoir, and the separator are positioned inthe casing.
 11. The system of claim 1, wherein the main reservoirincludes a main reservoir inlet, and the system further includes avented cap for closing the main reservoir inlet.
 12. The system of claim1, wherein a total volume of fluid circulating among the at least onebladder, the pump, the first fluid line, the second fluid line and theheat exchanger is a circuit volume, wherein the pump is positioned in acasing as part of a unit having a unit inlet in fluid communication withthe pump, and the pump, the unit inlet, and the separator are configuredand positioned in the casing such that the pump primarily draws fluidfrom the unit inlet and fluid is drawn from the separator by the pumponly when fluid is lost in the circuit volume
 13. A unit for providingheated or cooled fluid to an associated bladder to be placed on a bodypart, the unit comprising: a casing; a pump positioned in the casing,the pump including a pump inlet and a pump outlet; a heat exchangerpositioned in the casing and in fluid communication with the pump; aunit outlet in fluid communication the heat exchanger and positionedwith respect to the heat exchanger to receive fluid that has passedthrough the heat exchanger; a unit inlet in fluid communication with theheat exchanger and positioned with respect to the heat exchanger toprovide fluid to the heat exchanger; a main reservoir positioned in oron the casing; a separator positioned in the casing between and in fluidcommunication with the main reservoir and the pump, the separator beinglocated below the main reservoir to receive fluid under the influence ofgravity from the main reservoir, the separator being located withrespect to the pump so as to deliver fluid from the separator to thepump under the influence of gravity, wherein the separator is positionedin the casing such that fluid is drawn from the separator into the pumpinlet only when fluid is lost in a circuit between the unit inlet andthe unit outlet
 14. The unit of claim 13, further comprising a mainreservoir outlet line connected with an outlet of the main reservoir,wherein the separator has a separator inlet connected with the mainreservoir outlet line and defines volumetric space for allowing airbubbles to migrate toward a top of the separator without passing intothe main reservoir outlet line.
 15. The unit of claim 14, wherein themain reservoir has a maximum main reservoir volume and the separator hasa maximum separator volume, which is smaller than the maximum mainreservoir volume.
 16. The unit of claim 15, wherein the separator has alarger cross-sectional area as compared to a cross-sectional area of themain reservoir outlet line.
 17. The unit of claim 16, further comprisinga sensor configured to detect electrical current being drawn by thepump, and the pump is a centrifugal pump.
 18. The unit of claim 17,wherein the pump is upstream from the heat exchanger.
 19. The unit ofclaim 18, wherein the main reservoir includes a main reservoir inlet,and the unit further includes a vented cap for closing the mainreservoir inlet.